Container lock



May'23, 1944. .LDEsPoslro 2,349,707

CONTAINER LOCK Filed sept. 19. 1942 s sheets-sheet 2 www? May 23, 1944. J. DEsPosn-o Y GONT'AINER Locx Filed Sept. 19, 1942 3 Sheets-Sheet 5 Patented May 23, 1944 CONTAINER LOCK Julian DEsposito, Wilmette, lll., assignor to Container Corporation of America, Chicago, Ill., a corporation of Delaware Application September 19, 1942, Serial No. 458,975

o Claims. f (C1. 229-39) K This invention relates to devices for securing .twoplies of sheet material, such as relatively stiff paperboard, berboard, etc., in partially overlapping relationship in such a manner that they are Fig. l illustrates one end of a blank suitable for the production of a conventional carton or container of the tubular type in which two of the end closure naps are cut and scored in accordance capable of being detached from one another, but with a preferred embodiment of my invention; will not become completely disengaged except Fig. 2 shows a perspective view of the containunder exceptional stress. More particularly, it ers of Fig. 1 in set-up condition with the end relates to a locking device especially adapted for closure partially made; use with paperboard containers, such as rela- Fig. 3 is similar to Fig. 2, but illustrates the tively heavy folding cartons and solid nbre shipnext step in completing the closure; ping containers, which includes a safety feature Fig. l represents the Same Container With the such that the container will not open completely end closure completed and all of the locking eleeven if the primary locking element fails or ments in olJeratiVe position; becomes accidentally displaced. `I Fig. 5 is a partial view showing the relation- The locking device of my invention may be used l5 ship of the underlying looking elements When the in connection With any type of container closure Container is Closed; involving the partial overlapping of two plies of Fig. 6 illustrates the relationship of the locking paperboard or similar material. Examples 0f elements when the principal locking element has such closures are those using tuck flaps or tongues been removed from its operative position; and on cover panels or end flaps, and those in which Fig. 7 illustrates the manner in which the lock atleast two partially overlapping flaps are prois Completely disengaged So that the Container vided which are hingedly joined to opposite wall may he openedpanels. Numerous types of locks have, of course, While my inVention is adapted to be used in a been used or proposed in connection with these Variety 0f Situationsy it oen best be understood and similar types of container closures, and a from the description 0I" a SDeCiC eXample, and number of them are fairly adequate as long as the particular one chosen for this purpose is that vthey do not become dislodged from. their locking illustrated in the drawings.

position. In many instances, however, they do Fig. 1 shows one end of a container blank cut become so dislodged or weakened in handung or and Scored to provide four Side well panels I0, I I, shipment that the contents are exposed or lost. l2 and i3, an attaching strip I4 and four end One of the primary advantages of my invention Closure flaps l5, I6, ll and i3, hingedly attached is that the closure will retain a large measure of to Panels l0, ll, l2 and i3 along soole lines I9. its eiectiveness, even 'though the principal lock- 20, 2l end 22, TeSpeCtiVely- This blank is adapted ing element is aeeideni-,ally removed from its to be made into a conventional tubular container Joperative position, while the container can, nevhy Securing attaching Strip I4 to Panel l0 by ertneless, be opened easily and expeditiously when means of en adhesive, Staples or the Iike, and the it `is desired to do so without disturbing its useend 11ans are adapted to be folded into the usuel fulness for future use, manner to form an end closure, flaps I5 and I1 `It is an Object of my invention to provide a being folded rst, followed by flap I8 and nnallylocking arrangement for use in connection with 40 by flap l5- paperboard containers and the like, which can be 1n the Container 0f this eXamDle, it iS desired used to secure the closures of such containers to Secure flaps l5 and i3 together in partially quickly and easily, but which will prevent the overlapping relationship, and this iS accomaccidental opening of such container closures. Dlished by means of a looking arrangement ao- Another object is to provide a lock for paper- @Ording to the present invention The Pl'imaly board containers and the like which is formed'by looking element 23 is formed from the material suitably cutting and scoring the material of the of flap I8 and includes a tab 24 joined t0 ap I3 container, involves no extra operations in manualong Score line 25, Which iS parallel to score line facture, and is exceptionally eilicient in prevent- 22 and Separated therefrom by a distance Suoh ing accidental opening of the closure in connecthat when the container is set-up and flaps l5 tionwith which it is used. Further objects, adand I8 are overlapped, it will lie substantially in vantages and uses of my invention will be apparregister with indent 21 in the outer free edge of ent from the following detailed descriptionthereflap I6. Extending from the ends of score line of, readin conjunction withthe drawings, in 25 and substantially perpendicularly thereto in which: I 55 the direction of score line 22 are short cuts 26 free end of the latter. will be fully brought out as the description prowhich serve to allow score line 25 to be raised slightly above the plane of flap I8. Indent 21 is slightly longer than the distance between cuts 26, so that the base portion of tab 24 will enter and t rather snugly in indent 21 when the container is set up, as shown best in Figs. 4 and 5. This arrangement eiiectively interlocks flaps I5 and I8 against weaving motion, materially increases the effectiveness .of the primary locking element 23 by holding it always centered, and also strengthens the container itself against deformation from loads on its edges and corners.

Tab 24 is substantially in the form of an isosceles trapezoid with its sides converging toward the free end of ilap I8 and is provided along its outer side edges` with a pair of tongues 28 defined therefrom by angular score lines 29. The over-all length of tab 22 and tongues 28 is such that a strip of material 38 which is integral with flap I S remains immediately adjacent the outer The function of strip 35D ceeds.

Flap i5 is provided with a pair of angular cuts 3l diverging in the direction of its outer free ends and so located as to receive the tongues 28 and cooperate therewith to provide the primary con-V tainer lock. Extending toward, and perpendicular to score line 28 from the inner ends of cuts 3i, are two cuts 32 which terminate Vat points `slightly beyond the free end of iiapV I8 when flaps I6 and i8 are overlapped, and a score line 33 is also provided between cuts 32 somewhat short of the ends thereof and also slightly be yond the end of ap I8. An additional Vcut 34, extending between cuts 3i at approximatelytheir points -of closest approach, defines a tab member `35, formed from the material of flap I, which is hingedly joined thereto along score line` 32. Cut 22' is non-rectilinear and is arranged so that tab 35 has a notch in its free edge whereby a tab 35 is formed which is integral with iiap I6 and extends toward score line lil. Tab 35 in this particular embodiment of the invention, is rectangular in shape and it constitutes one of the secondary ylocking elements. For this reason, it is or" such length that its free end extends slightly beyond the inner edge of strip 38 when fiaps it and I8 Iare overlapped, for reasons which will be discussed more fully.

In utilizing my invention as illustrated by the presently preferred form thereof shown in the drawings, the blank of IlV is formed into a tubular container by attaching strip vlf3. to wall panel It in any conventionalvmanner such as by gluing or stapling. If we assume that flaps l5, It, il', and I8 are top closure flaps, the bottom of the container which can be but is not necessarily oi conventional construction, is closed and the container filled with the desired product. Flaps i5 and. l1 are then :folded toward each other substantially at right angles to their .respective side walls lll and i2, and flap. It is partially folded in the same manner, while tab 35 is pressed slightly downward so that its free ends lie somewhat below the plane of flap Iii. In this stage, the container appears as shownin Fig. 2.

The next step is to bend tabk 2.4 with its associated tongue elements upwardly along score of flaps I8 and I8 is then continued until they are in partially overlapped condition and substantially parallel to flaps I5 and I1. The appearance of the top closure, just before the folding last mentioned is completed, is illustrated in Fig. 3. Finally, tongues 28 are bent inwardly along score lines 29, and are inserted into the .slits 3i as tab 24 is brought substantially into the plane of flap I5, a slight pressurethen being exerted upon tab 24 adjacent the center portion of its free end. The completely closed container is illustrated in Fig. 4.

Some of the advantages of this form of lock have already been mentioned, the primary locking elements including tab 24, tongues 28 and slits 3l being, of course, old in the art. It will be noted, however, that the cooperation between the base of tab 22 adjacent score line 25 and the indent 21 substantially prevents relative motion of flaps I6 and I8 in a direction parallel to score line 25 and thus materially strengthens the top closure and the container itself. Furthermore, the fact that tab 35 is held beneath its normal level provides a separation space between flap it and the underlying iiaps I5 andl I1, so that tongues 2t can be much more easily inserted in slits 3i.

One of the major advantages, however, arises from the secondary locking arrangement involving strip 32 and tab 35. As stated above, tab 35 is of such length that it extends slightly beyond the inner edge of strip 2B, so that when pressure is applied to tab 2li adjacent the middle of its free edge in making the closure, this pressure is transmitted to tab S5 and the latter is caused to snap into position below strip 3l). The relationship of these parts when the completed closure has been made is clearly shown in Fig. 5. rThe arrangement just described provides a lock which is effective even though tongues 28 should be accidentally Vdislodged for some reason, or if the primary lock should be defective and fail. If lone of these eventua'lities occurs and aps I6 i8 should tend to open, strip 30 will' ride 1' up upon tab 35 as shown in Fig. 6 and. these aps will be able to open only a limited. distance before they are held in substantially the position shown in that iigure. Due to the fact that the angle oi movementY through which iiaps IB and `it may go is quite limited, aps I5 and I1 will be retained in substantially their completely closed position and danger of the loss of the contents is thereby minimized.

In `order to open the container when it isv desired to do so, it is only necessary to bend tab 24 upwardly so that tongues 28 are withdrawn from slits 3l and press down upon strip V30 so that tab 36 snaps to a position above it as shown in Fig. "1. Thereafter, iiaps I6 and I8 may be swung up.- wardly without hindrance, followed by iiaps4 I5 `and I1.

It will be apparent from the above that I have devised a novel form of container lock which has many advantages and which is. extremely useful inmany situations, and it is equally obviousthat many modifications may be made therein. by those skilled in the art without departing from the spirit of my invention. While the invention vhas been described by way of example Vin connection with a single embodiment thereof, it is not desired to be limited thereto, but by only the scope of the appended claims.

I claim:

1. In a container made of sheet materialfsuch as paperboard or the like and having a closureincluding two plies of said material, at least one of said plies being arranged to swing about a score line or the like so that in closed position said plies overlap each other by a substantial amount, the improved locking arrangement for said closure which comprises a tab having laterally extending tongue portions partially cut from the material of the lower ply and `integrally joined thereto along a hinge line substantially parallel to said score line, said cut being spaced from the free edge of said lower ply so as to leave a strip of said material adjacent said edge and said tab being adapted to overlie the upper ply of said material, a pair of elongated openings in said upper ply adapted to receive said tongue portions, and additional tab means formed from said upper ply including at least one tab having its free end extending toward and one tab having its free end extending away from the freel end of said upper ply, said last-mentioned tabs being defined by a non-rectilinear out extending between said elongated openings and being arranged so that during the closing operation said strip may pass over said tab having its free end extending toward the edge of said upper ply and will thereafter be engaged by said tab extending in the opposite direction if said tongue portions should become accidentally dislodged from said openings.

2. The improvement according to claim l wherein said elongated openings in said upper ply diverge in the direction of the free end thereof.

y3. The improvement according to claim 1 including a recess in the free edge of said upper ply adapted to receive said locking tab substantially at its base portion adjacent said hinge line, whereby relative lateral movement of said plies is prevented.

4. An improved locking arrangement for a container of paperboard or the like having a pair of oppositely disposed side walls and a closure flap hingedly joined to each of said side walls at one end of said container and wherein said closure flaps are adapted to overlap over a substantial area adjacent their free ends comprising a looking tab formed from the material of the lower of said overlapping ilaps hinged thereto along a score line substantially in register with the free end of the upper of said flaps and being adapted to be folded to lie above said upper flap, said locking tab having laterally extending tongue portions defined by a pair of inclined fold lines converging toward its end and being substantially shorter than the distance between said score line and the free end of said lower flap, whereby a strip of material remains adjacent the free end of Said lower flap, a pair of slits in said upper ap substantially parallel to and slightly laterally spaced from said fold lines adapted to receive said tongue portions to ho-ld said flaps in closed position, and a pair of secondary tabs formed n from that portion of the material of said upper flap lying between said slits, one of said secondary tabs being hingedly joined to said upper ap along a score line substantially parallel to but slightly beyond the free end of said lower ap when said aps are in closed position and being adapted to be depressed so that said strip can be passed thereover in closing said aps, and the other of said secondary tabs extending away from the free end of said upper flap to a point slightly beyond the inner edge of said strip, whereby slight pressure on said locking tab after said tongue portions have been inserted in said slits will cause the free end of last-mentioned secondary tab to assume a position below said strip. l

5. An improved locking arrangement according to claim 4 including a recess in the free edge of said upper flap adapted to receive said locking tab adjacent its hinge liner, whereby lateral movement of said flaps with respect to each other is minimized.

6. An improved locking arrangement for a container of paperboard or the like having a pair of oppositely disposed side walls and a closure flap hingedly joined to each of said side walls at one end of said container and wherein said closure aps are adapted to overlap over a substantial area adjacent their free ends comprising a locking tab formed from the material of the lower of saidl overlapping fiaps hinged thereto along a score line substantially in register with the free end of the upper of said aps and being adapted to be folded to lie above said upper ap, said locking tab having laterally extending tongue portions defined by a pair of inclined fold lines converging toward its end and being substantially shorter than the distance between said score line and the free end of said lower flap, whereby a strip of material remains adjacent the free end of said lower flap, a pair of slits in said upper ilap substantially parallel to and slightly laterally spaced from said fold lines adapted to receive said tongue portions to hold said flaps in f closed position, and a recess in the free edge of said upper flap adapted to receive said locking tab adjacent its hinge line, whereby lateral movement of said flaps with respect to each other is minimized.

JULIAN DESPOSITO. 

